The insufflation of freon in vitreoretinal surgery

Among the various gases recommended for intravitreal injection, sulfur hexafluoride (SF6) and octafluorocyclobutane (C4F8) are the most commonly used. The purpose of the injection is to restore the vitreous chamber after drainage of subretinal fluid or after vitrectomy. Some of the fluorinated hydrocarbons which belong to the group known as Freon (a registered trademark) have previously been used in the animal with the same end in view. Of these, Freon-12 and Freon-114 were selected on account of their physical properties, the fact that they remain in the vitreous cavity for 4-14 days, their availability and their innocuousness, and used in humans as an adjunct to vitreoretinal surgery. The results are compared to those obtained with other halogenated gases.